Sheet metal piercing



A. E. HUTT 2,467,034 SHEET METAL PIERCING 2 Sheets-Sheet 1 April 12, 1949.

Filed Nov. 20, 1945 INVENTOR.

a f J v w 6 22:2: f M m .u M i H m/ A k A. E. HUTT SHEET METAL PIERCING April 12, 1949.

2 Sheets-Sheet 2 Filed Nov. 20, 1945 We. a; 49/7 8 JILBE/Pr E Hurr- INVENTOR.

Patented Apr. 12, 1949 SHEET METAL PIERCING Albert E. Hutt, Stamford, Conn., assignor, by mesne assignments, to Schick Incorporated, a corporation of Delaware Application November 20, 1945, Serial No. 629,735

3 Claims.

This invention relates to an improved form of press suitable for carrying out the method of piercing sheet material disclosed in my application Serial No. 588,153, filed April 13, 1945, now Patent 2,395,123, granted February 19, 1946.

In that application there is disclosed a method of piercing sheet material, such as thin sheet metal, by means of hydraulic pressure. In general, such method contemplates the use of a rigid following description.

position.

the sheet 4.

which are seated in the piston 8.

unsupported areas of the sheet 4.

any suitable power mechanism, not shown.

consists of a body portion I'I having a conical upper end adapted to seat against the shoulders 58 of an insert I9 in the head of piston 8 to close oif communication between cylinders II and I4. The valve body is biased to its closed position, as by a spring 20, the lower end of which seats on a spider 2|. A passage 22 extends upwardly through the valve body, but it, too, is normally closed, as by ball 23.

sheet support which is recessed or provided with 1 I th operation f the press, the trough 2 is ap r r s a ely sh p d d l c e o efi filled with liquid, such as oil, to the level indicated the precise areas to be pierced, the sheet bein at 24, and the space beneath and around the lower la d o the pp t and its -p Surface then end of piston 8 is likewise filled with liquid, as are Subj te t q d Pressure in an amount also the cavity I2 and cylinder sections II and I4. ficie t t r p e the unsupported area-S 0f the With a sheet such as 4 in position to be pierced, sheet. The present invention provides a simplipressure is applied to plunger I5 and thereby to fled fo m o p e s Will be pp from the the liquid in cylinder I4, and the head of piston 8. The springs 9 and the valve spring are so In the accompa draWmgS, in Which a related that the former yield before the latter preferred f m of e improved press 20 with the result that, as plunger I5 is depressed, trated, Fig. 1 is a vertical section; Fig. 2 is an enthe pressure developed in th liquid i cylinder larged broken out view of the control valve; and M serves first to depress i t 3 bodily t th Fig. is a ve tica s ct o similar 130 1 but position indicated in Fig. 3 where it is in clamping S o Certain of the parts 1Y1 a dlfierent engagement with sheet 4. Under increasing pressure of the liquid in cylinder I4, valve I3 is de- In Flgs- 1 and 2 1711? Press 15 shown conslstmg pressed and opens and the compressive force of Of a base or P I rlglqly suppfllted 111 a trough plunger I5 is transmitted to the liquid column in 2, the base incorporating an insert or block 3 cylinder H and to the upper surface of Sheet 4 Which Serves as a Support for the Sheet 4 to Under increasing pressure and in due course the pierced. This support is pierced. or provided with Sheet is ruptured at each its unsupported aieas 2 11:33 tags???b?p g gfc ggg gi gufio g Thereafter, and as plunger I5 is relieved ti the y s 1 A e I Q of illustration, the block 3 is shown provided with g; zfiific fi g s i 3 c lg s e s a i r i g i r i li l six holes 5, the upper or entrance ends of which moves g the position of Fig fi gs: define the outline of six holes to be pierced in Created by the r movemen't plunger |5 raises ball 23 and cylinder I4 is, accordingly, re- 5 if xg gg g s ggjgg 2 plenished by the suction-induced, upward flow of movably mounted in the lfltter 2 a 3 8 liquid from cylinder II. When plunger I5 reaches which normally, or when press ispidle is m the upper limit of its stroke and comes to rest, biased into the upper position indicated in Fig. 1. E? 23 f i passage'cmsmg For this purpose, springs 9 are shown abutting a .0 e p-arts th-en restored to the lower nd f t d m h the position indicated in Fig. 1 w1th the several e s 0 S u S t e g s of passages wholly filled with liquid in readiness incorporates a cylinder I I which, at its lo 213; t ffi ifig d d terminates in a cavity I2 which overlies all of the apparatus is g i i ggfli igg g viously be applied in a variet o P head or uppel: end of plston 8 15 mounted scope of the invention will be ur id ii tzo d o a valve, generally designated I3; and above the d fi d by the followin 01 im valve and piston head is a second cylinder section I claim. g a

in which operates a plunger I5. The latter is r -mt in ..i-.5:.:.rr:uisii iii are; its; Sprmg and 15 adapted to be depressed by having an aperture serving to deprive of support the area of the sheet to be pierced, a cylinder As shown more particularly in Fig. 2, valve I3 mounted on thebed, a piston movable in the cylinder into engagement with the sheet to clamp the same against the bed, said piston incorporating a liquid-containing cylinder terminating in a cavity overlying the unsupported area of the sheet and adapted to be closed by the sheet when the piston is in engagement therewith, the combination therewith of an upper liquid-containing cylinder section'closed at its lower end by the head of the piston and at its upper end by a plunger, whereby depression of the plunger moves the piston into sheet-clamping position, a downwardly-opening, spring-supported valve mounted in the head of the piston and fadapted to be opened in response to further depression of the plunger to admit the pressure of the liquid above the valve to said first-mentioned liquid containing cylinder, and a normally-closed ball valve carried by the spring-supported valve, said ball-- valve being adapted to open in response to -upward movement of 'the'pluriger and permit the suction-replenishment of said taining' cylinder sec'tiom upper, liquidcon- 2. In a press having a bed forming a sup- 'port 'for a'sheet to be pierced, thesurface of the bed having aniaperture servin to deprive of support the area of the sheet to be pierced; a cylinder mounted on the bed, a; piston movable'in the cylinder into engagement with the sheet to clamp the same against the .bed, said piston incorporating a liquid-containingcylinder terminating in a eavityoverlying the unsupported-area of the sheet and adapted to becl'o'sedby the'sheet when the piston is inengagement therewith, the combination therewith'ot'an upper, liquid-containing cylinder sectionolosed at its lower end by the head-of the piston and/at its'upper end by a plunger, whereby depression "of the plunger moves plunger to admit the pressure of the liquid above the valve to said first-mentioned liquid-containing cylinder, and a normally-closed valve adapted to open in response to upward movement of the plunger, said last-mentioned valve controlling liquid flow from the first-mentioned liquid-containing cylinder to said upper, liquid-containing cylinder.

3. In a press having a bed forming a support for a sheet to be pierced, the surface of the bed having an aperture serving to deprive of support the area of the sheet to be pierced, a cylinder mounted on the bed, a piston movable in the cylinder into engagement with the sheet to clamp the same against the bed, said piston incorporating a'liquid-containing cylinder terminating in a cavity overlying the unsupported area of the sheet and adapted to be closed by the sheet when the piston is in engagement therewith, the combination therewith of an upper liquid-containing cylinder section closed at its lower end by the head of the piston and at its upper end by a plunger, whereby depression of the plunger moves the piston into sheet-clamping position, valve means adapted to open in response to further depressionrof the plunger to admit the pressure of the'liquid in said upper, liquid-containing cylinder section to said first-mentioned liquid-containing cylinder, and means for replenishing said upper, liquid-containing cylinder following closure of said valve means.

ALBERT E. I-IU'IT.

REFERENCES CITED H "'The following references are of record in the file of this patent:

- UNITED STATESHPATENTS Number Name Date 2,395,123 Hutt Feb, .19, 1946 

